16,697 research outputs found

    The Mystery of Capital and the Construction of Social Reality

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    John Searle’s The Construction of Social Reality and Hernando de Soto’s The Mystery of Capital shifted the focus of current thought on capital and economic development to the cultural and conceptual ideas that underpin market economies and that are taken for granted in developed nations. This collection of essays assembles 21 philosophers, economists, and political scientists to help readers understand these exciting new theories

    Ontology of common sense geographic phenomena: Foundations for interoperable multilingual geospatial databases

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    Information may be defined as the conceptual or communicable part of the content of mental acts. The content of mental acts includes sensory data as well as concepts, particular as well as general information. An information system is an external (non-mental) system designed to store such content. Information systems afford indirect transmission of content between people, some of whom may put information into the system and others who are among those who use the system. In order for communication to happen, the conceptual systems of the originators and users of the information must be sufficiently similar. A formal conceptual framework that can provide the basis for exchange of information is termed an ontology. In its most fundamental form, ontology studies the most basic constituents of reality. Traditionally, ontology seeks to reflects structures that are independent of thought and cognition. The term ontology is used more broadly in artificial intelligence and software engineering, to refer to the conceptual basis for an information system

    A Slave No More: Two Men Who Escaped to Freedom, Including Their Own Narratives of Emancipation

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    Narratives of Bondage David W. Blight, author of the award-winning Race and Reunion (2001), director of Yale University\u27s Gilder Lehrman Center for the Study of Slavery, Resistance, and Abolition, and arguably one of the world\u27s most distinguishedùand certainly one of the most insig...

    Hard x-ray polarimetry with the Ramaty High Energy Solar Spectroscopic Imager (RHESSI)

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    Although designed primarily as a hard X-ray imager and spectrometer, the Ramaty High Energy Solar Spectroscopic Imager (RHESSI) is also capable of measuring the polarization of hard X-rays (20-100 keV) from solar flares. This capability arises from the inclusion of a small unobstructed Be scattering element that is strategically located within the cryostat that houses the array of nine germanium detectors. The Ge detectors are segmented, with both a front and rear active volume. Low energy photons (below about 100 keV) can reach a rear segment of a Ge detector only indirectly, by scattering. Low energy photons from the Sun have a direct path to the Be and have a high probability of Compton scattering into a rear segment of a Ge detector. The azimuthal distribution of these scattered photons carries with it a signature of the linear polarization of the incident flux. Sensitivity estimates, based on simulations and in-flight background measurements, indicate that a 20-100 keV polarization sensitivity of less than a few percent can be achieved for X-class flares

    The Inability of Ambipolar Diffusion to set a Characteristic Mass Scale in Molecular Clouds

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    We investigate the question of whether ambipolar diffusion (ion-neutral drift) determines the smallest length and mass scale on which structure forms in a turbulent molecular cloud. We simulate magnetized turbulence in a mostly neutral, uniformly driven, turbulent medium, using a three-dimensional, two-fluid, magnetohydrodynamics (MHD) code modified from Zeus-MP. We find that substantial structure persists below the ambipolar diffusion scale because of the propagation of compressive slow MHD waves at smaller scales. Contrary to simple scaling arguments, ambipolar diffusion thus does not suppress structure below its characteristic dissipation scale as would be expected for a classical diffusive process. We have found this to be true for the magnetic energy, velocity, and density. Correspondingly, ambipolar diffusion leaves the clump mass spectrum unchanged. Ambipolar diffusion appears unable to set a characteristic scale for gravitational collapse and star formation in turbulent molecular clouds.Comment: 16 pages, 5 figures. ApJ accepte
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